Weather on August 21
Chicago, IL
55 Years of Data
Avg High
81°F
Avg Low
66°F
Warmest
2003
86°F avg
Coldest
1997
64°F avg
About This Date
August 21st in Chicago, IL typically brings warm summer weather, with average highs around 81°F and lows near 66°F. Over 53 years of records, the warmest August 21st was in 2003 (86°F average), while the coldest was 1997 (64°F) — a 22°F range across recorded history. Rain or other precipitation has occurred on about 13% of August 21st dates historically, with the wettest August 21st recording 1.09" of rain. Temperatures on this date have remained relatively stable over the past several decades.
Temperatures on this date have remained relatively stable over the past several decades.
Planning for August 21st in Chicago, IL? Stay hydrated and seek shade during peak afternoon hours.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2025 | 74° | 69° | 71° | — | — |
| 2024 | 72° | 61° | 66° | — | — |
| 2023 | 83° | 71° | 77° | — | — |
| 2022 | 74° | 68° | 71° | — | — |
| 2021 | 89° | 74° | 81° | — | — |
| 2020 | 83° | 70° | 76° | — | — |
| 2019 | 83° | 69° | 76° | — | — |
| 2018 | 76° | 68° | 72° | — | — |
| 2017 | 84° | 71° | 78° | — | — |
| 2016 | 76° | 62° | 69° | — | — |
| 2015 | 82° | 62° | 72° | — | — |
| 2014 | 77° | 70° | 73° | — | — |
| 2013 | 91° | 72° | 81° | — | — |
| 2012 | 78° | 64° | 71° | — | — |
| 2011 | 83° | 70° | 76° | — | — |
| 2010 | 82° | 70° | 76° | — | — |
| 2009 | 77° | 60° | 69° | — | — |
| 2008 | 81° | 72° | 76° | — | — |
| 2007 | 84° | 70° | 77° | — | — |
| 2006 | 80° | 65° | 72° | — | — |
| 2005 | 79° | 70° | 74° | — | — |
| 2004 | 75° | 59° | 67° | — | — |
| 2003warmest | 97° | 75° | 86° | — | — |
| 2002 | 89° | 66° | 78° | — | — |
| 2001 | 80° | 61° | 70° | 0.33" | — |
| 2000 | 81° | 59° | 70° | — | — |
| 1999 | 76° | 58° | 67° | — | — |
| 1998 | 91° | 71° | 81° | — | — |
| 1997coldest | 72° | 57° | 64° | — | — |
| 1994 | 78° | 65° | 71° | 0.51" | — |
| 1993 | 78° | 69° | 74° | — | — |
| 1992 | 78° | 57° | 68° | — | — |
| 1991 | 80° | 59° | 70° | — | — |
| 1990 | 72° | 67° | 69° | 0.94" | — |
| 1989 | 85° | 65° | 75° | — | — |
| 1988 | 80° | 70° | 75° | — | — |
| 1987 | 84° | 67° | 75° | 1.09" | — |
| 1986 | 85° | 64° | 74° | — | — |
| 1985 | 73° | 60° | 67° | — | — |
| 1984 | 84° | 61° | 72° | — | — |
| 1983 | 94° | 71° | 82° | — | — |
| 1982 | 83° | 66° | 74° | — | — |
| 1981 | 79° | 62° | 70° | — | — |
| 1980 | 93° | 70° | 81° | 0.53" | — |
| 1979 | 78° | 67° | 72° | — | — |
| 1978 | 78° | 58° | 68° | 0.1" | — |
| 1977 | 75° | 64° | 70° | 0.23" | — |
| 1976 | 80° | 71° | 76° | — | — |
| 1975 | 92° | 69° | 80° | — | — |
| 1974 | 86° | 72° | 79° | — | — |
| 1973 | 71° | 67° | 69° | — | — |
| 1972 | 89° | 75° | 82° | — | — |
| 1971 | 89° | 70° | 79° | — | — |
53 years of data from CHICAGO GRANT PARK